Branching Strategy in Github Repo

I'm looking to start building Swift on RISC-V and am trying to get my bearings on the branching strategy used in the main swift repo. Is main Swift 5.8 development, or is there a develop branch? Would one branch from release/5.7 if they wanted to start there? Any pointers would be appreciated!

Check out the official branching doc, main is currently 5.9. Which branch you use depends on what you want, my recommendation is to check out the latest trunk snapshot tag (ie not one of the 5.8 ones), as those have passed the CI.

Perfect, exactly what I was looking for and thank you!